United States	AuqilSt 2016
Environmental Protection	°
Agency	EPA 430-F-16-034
What Climate Change
Means fortyew York
New York's climate is changing. Most of the state has
warmed one to three degrees (F) in the last century,
heavy rainstorms are more frequent, and the sea is rising
about one inch every decade. Higher water levels are
eroding beaches, submerging low lands, and exacerbating
coastal flooding. In the coming decades, changing the
climate is likely to increase coastal and inland flooding,
disrupt farming and winter recreation, and increase some
risks to human health.
Our climate is changing because the earth is warming.
People have increased the amount of carbon dioxide in
the air by 40 percent since the late 1700s. Other heat-
trapping greenhouse gases are also increasing. These
gases have warmed the surface and lower atmosphere of
our planet about one degree during the last 50 years.
Evaporation increases as the atmosphere warms, which
increases humidity, average rainfall, and the frequency of
heavy rainstorms in many places—but contributes to
drought in others.
Greenhouse gases are also changing the world's oceans
and ice cover. Carbon dioxide reacts with water to form
carbonic acid, so the oceans are becoming more acidic.
The surface of the ocean has warmed about one degree
during the last 80 years. Warming is causing snow to melt
earlier in spring, and mountain glaciers are retreating.
Even the great ice sheets on Greenland and Antarctica are
shrinking. Thus the sea is rising at an increasing rate.
Increasing Temperature and Changing Precipitation Patterns
Rising temperatures and shifting rainfall patterns are likely to increase the intensity of
both floods and droughts. Average annual precipitation in the Northeast has increased
10 percent since 1895, and precipitation from extremely heavy storms has increased
70 percent since 1958. During the next century, annual precipitation and the fre-
quency of heavy downpours are likely to keep rising. Precipitation is likely to increase
during winter and spring, but not change significantly during summer and fall. Rising
temperatures will melt snow earlier in spring and increase evaporation, and thereby
dry the soil during summer and fall. As a result, changing the climate is likely to
intensify flooding during winter and spring, and drought during summer and fall.
Rising Sea Level
Sea level is rising more rapidly along New York's coast than in most coastal areas
because the land surface is sinking. If the oceans and atmosphere continue to warm,
tidal waters in New York are likely to rise one to four feet iri the next century.
As sea level rises, the lowest dry lands are submerged and become either tidal wetland
or open water. Wetlands can create their own land and keep pace with a slowly rising
sea. But if sea level rises three feet or more during the next century, most existing
wetlands along the south shore of Long Island are likely to be submerged.
Coastal Storms
Rising sea level increases the vulnerability of coastal homes and infrastructure to
flooding because storm surges become higher as well. Although hurricanes are rare,
much of the infrastructure in the New York metropolitan area is vulnerable to flooding.
In 2012, high waters during Hurricane Sandy flooded Amtrak, PATH, and subway
tunnels, as well as electrical substations, wastewater treatment plants, telecommuni-
cation facilities, hospitals, and nursing homes. Wind speeds and rainfall rates during
hurricanes and tropical storms are likely to increase as the climate warms. Rising sea
level is likely to increase flood insurance premiums, while more frequent storms could
increase the deductible for wind damage in homeowner insurance policies.
Temperature change (°F):
Breezy Point, Queens, in the aftermath of an electrical fire ignited by floodwaters during
Hurricane Sandy. Credit: Andrea Booher, FEMA.
Rising temperatures in the last century. The eastern part of
New York has warmed more than the western part of the state.
Source: EPA, Climate Change Indicators in the United States.

Bird feeding on invertebrates that inhabit
a tidal beach vulnerable to rising sea level
along Peconic Bay in Riverhead.
© James G Titus; used by permission.
Shoreline Erosion
Beaches also erode as sea level rises. A higher ocean level makes it more
likely that storm waters will wash over a barrier island or open new inlets.
The United States Geological Survey estimates that the barrier islands in
Southampton would be broken up by new inlets or lost to erosion if sea
level rises three feet by the year 2100, unless people take measures to
reduce erosion.
Coastal Ecosystems
Rising sea level could disrupt
ecosystems along the Atlantic
Ocean and adjacent estuaries
such as the Hudson River and
Long Island Sound. Wetlands
threatened by rising sea
level currently support clapper
rail, sharp-tailed sparrow,
marsh wren, and the northern
harrier, a threatened species.
Beaches along Long Island
Sound and other estuaries
may be squeezed between
development and the advancing
sea. Those beaches provide nesting sites for horseshoe crabs, which are
a key source of food during spring for migrating shorebirds, such as the
endangered red knot. Other shorebirds feed on these beaches throughout
the year. Vulnerable tidal flats provide habitat for soft clam, hard clam, bay
scallop, and blue mussel.
The Great Lakes
Lake ecosystems may also be impaired as the climate changies. Warmer
temperatures tend to cause more algal blooms, which can be unsightly,
harm fish, and degrade water quality. If severe storms become more
frequent, then sewer overflows will become more frequent, and more pol-
lutants are likely to run off from the land into the Great Lakes. Increased
algal blooms and water pollution could threaten water supplies and
require recreational beaches to be closed more often for health reasons.
One advantage of climate change is that warmer winters reduce the
number of days that ice prevents navigation on rivers and in the Great
Lakes. Between 1994 and 2011, reduced ice cover lengthened the
shipping season on the Great Lakes by eight additional days. The Great
Lakes are likely to warm another 3° to 7°F in the next 70 years, which will
further extend the shipping season.
Winter Recreation
Warmer winters may bring more rain and less snow to upstate New
York. A decline in snowfall would mean less snow cover for recreational
industries, like skiing, snowboarding, and snowmobiling, and it would
harm the local economies that depend on them. Conversely, the amount
of lake effect snow has increased with the longer ice-free season on the
Great Lakes. Although scientists are not certain whether this trend will
continue, increased snow would benefit winter recreation areas to the
immediate east of Lake Erie and Lake Ontario.
Changing the climate will have both beneficial and harmful effects on
farming, but the net effect is unknown. During an average year, longer
frost-free growing seasons and higher concentrations of atmospheric
carbon dioxide would increase yields for many crops, notably soybeans.
But increasingly hot summers are likely to reduce yields of corn, the
state's most important crop. Higher temperatures cause cows to eat less
and produce less milk, so a warming climate could reduce the output of
milk and beef, which together account for more than half the state's farm
Human Health
Climate change is likely to amplify some threats to human health. Higher
temperatures can increase the formation of ground level ozone, a pollutant
that can contribute to respiratory problems. Rising temperatures may also
increase the length and severity of the pollen season for plants such as
ragweed. Certain people are especially vulnerable, including children, the
elderly, the sick, and the poor.
The risk of some diseases carried by insects may also increase. The ticks
that transmit Lyme disease are active when temperatures are above 45°F,
so warmer winters could lengthen the season during which ticks can
become infected or people can be exposed to the ticks. Higher tempera-
tures would also expand the area that is warm enough for the Asian tiger
mosquito, a common carrier of West Nile virus. The number of cases may
or may not increase, depending on what people do to control insect
populations and avoid insect bites.
Increase in Lyme disease between 1996 and 2013. Each dark dot shows one
case reported in 1996; light dots show 2013. The increased range of the disease
has been attributed to factors other than climate change. Nevertheless, additional
warming will lengthen the season during which people are exposed to Lyme
disease and may allow the disease to spread to colder areas. Source: CDC.
The sources of information about climate and the impacts of climate change in this publication are: the national climate assessments by the U.S. Global Change Research
Program, synthesis and assessment products by the U.S. Climate Change Science Program, assessment reports by the Intergovernmental Panel on Climate Change, and EPA's
Climate Change Indicators in the United States. Mention of a particular season, location, species, or any other aspect of an impact does not imply anything about the likelihood or
importance of aspects that are not mentioned. For more information about climate change science, impacts, responses, and what you can do, visit EPA's Climate Change website
at www.epa.aov/climatechanae.